Extreme Weather Events on the Rise

Can scientists now say with a fair amount of confidence that extreme weather events such as the Texas heat wave last year, the Russian heat wave of 2010 and the European heat wave of 2003 are directly linked to global warming caused by humans?

In a new paper entitled ‘Perception of Climate Change’ NASA scientist James Hansen and two colleagues describe how climate change has increased the occurrence of unusually warm weather events in the past 30 years. There is only a small chance that the shift towards both higher temperatures and increased weather extremes would have happened in the absence of climate change.  Periods of extreme summertime temperatures have increased in geographic scope from less than 1% of the land’s surface in the base period of 1951 to 1980 to covering 13% in recent years.